edmunds



(No Model.) 4 Sheets-Sheet 1.

H. EDMUNDS.

SYSTEM OFUTILIZING SECONDARY BATTERIES. No. 390,464. Patented Oct. 2, 1888.

F|6 l PIC-3-3 F|G 5 4 SheetsSheet 2.

(No Model.)'

H. EDMUNDS.

SYSTEM OF UTILIZING SECONDARY BATTERIES. No. 390,464.

Patented Oct. 2, 1888. FIG -7 4 Sheets-Sheet 3.

H. EDMUNDS.

SYSTEM OF UTILIZING SECONDARY BATTERIES. No. 390,464.

(No Model.)

Patented Oct. 2, 1888.

N. PETERS. Fholmumngmpngr. Washingon. Dvc

(No Model.) 4 Sheets-Sheet 4.

H. EDMUNDS.

SYSTEM OF UTILIZING SECONDARY BATTERIES.

No. 390,464. Patented Oct. 2, 1888.

UNITED STATES PATENT HENRY EDMUNDS, OF LONDON, ENGLAND.

SYSTEM OF UTILIZING SECONDARY BATTERlES.

SPECIFICATION forming part of Letters Patent No. 390,464, dated October 2, 1888.

Original application filed June 21. 1888, Serial No. 277,712. Divided and this application filed July 16, 1888. Serial No. 280,019. (No model.) Patented in England June 15, 1887, No. 8,641.

To all whom it may concern.-

Be it known that I, HENRY Ennunns, of London, England, have invented a new and useful Improvement in Systems for Utilizing Secondary Batteries, (for which lhave obtained Letters Patent in Great Britain, No. 8,641, dated June 15, 1887.) which improvement is fully set forth in the following specification.

lhis invention has reference more particularly to the utilization of secondary or storage batteries for electric lighting and similar purposes; in installations which include a charging dynamo or dynamos at a central station and groups of batteries at sub stations or localities where their energy is to be utilized; a charging main; local or utilization circuits at each substation; and means whereby the batteries may be transferred from the main to the local circuit, and vice versa, for charging and discharging.

Herctofore and prior to my invention it has been common to provide at each station or point of use two sets of batteries, one of which may be receiving its chargein the main while the other is supplying the utilizationcircuit, automatic switch mechanism being employed to transfer the sets of batteries from one circuit to the other. The object of such system is to maintain the supply of the utilization-circuit constant, there being always one set of batteries in condition to supply the required energy. It will be observed that the use of such system requires at each station twice the number of batteries actually needed to supply the lamps or other translating devices. The power of the charging-dynamo must be sufficient to charge at once half of all the batteries used-in other words, to supply at all times an amount of energy somewhat in excess of the maximum energy used in the entire system. Excessive leakage and danger to life are necessary incidents of such system. Each set or group of batteries remains in the local circuit until practically exhausted, the potential of the circuit being greatest when a freshlycharged group of batteries is switched in, and thereafter steadily falling as they discharge. This fluctuation causes inconveniences to the consumers, and the strain produced thereby upon the lamps militates against their longevity. It is obvious that as the minimum potential of the circuits must be sufficient to maintain the light if it be a lighting system) the maximum potential will be greatly in excess. A waste of energy is therefore involved.

By the present invention the losses, dangers, and inconveniences above referred to are prevented, and other important practical advantages are secured, as hereinafter set forth. According to my invention the batteries at each station or point of utilization are divided into three or more sets or groups, containing each the same number of cells. I [ind it con venient to use fourgroups at each station, and shall describe, for the sake of example, asystern employing that number, though it is obvious that the invention is not limited thereto. These groups or sets are one by one, for short and equal periods of time, switched into the charging-main, so that there will always be one set in the chargingmain, while threefourths of all the batteries employed will be supplying the local or working circuit. The system therefore calls for only two-thirds the number of batteries that would be required in the system above referred to; and as the batteries are perhaps the most costly part of such an installation this saving is of greatinlportance. Proportionally less power and smaller generating plant are also required, since only onefourth, instead of half, the total number of batteries is in the main or charging circuit. Besides the economy thus caused there results the important advantage of smaller leakage, due to the lower pressure employed and less danger to life. The batteries, moreover, are not charged to their maximum capacity and then completely discharged, but are maintained in nearly a uniform condition. For e3:- ample, there being four sets of batteries, and the period of inclusion of each set in the charging-circuit being fixed at two minutes, each battery will be withdrawn from the workingcircuit once in every eight minutes for fresh charge. This is found to increase greatly the efliciency of the batteries and to retard deterioration. It also produces an important effect iii the working'circuit, the pressure in which is, by means of this invention, kept practically uniform, whereby the longevity of the lamps is greatly increased.

There being no fluctuation, such as above referred to, in estimating the number of cells necessary to do the work of any particular station this consideration may be disregarded, and no margin of waste energy need be allowed to prevent the minimum potential falling below the limit required, as necessary heretofore.

If the batteries at the several stations are charged in series, it may be desirable to utilize the main or charging circuit for other work in addition to the charge of the batteries. The invention permits this to be done, since the charging-circuit is not interrupted nor the potential materially affected by the operations performed in carrying out this invention.

It is essential to the best working of such a system and to the attainment of all the advantages above pointed out that the changes of each set of batteries from the working to the charging circuit should be effected in such manner that, first, no portion of the battery is in connection with both circuits at the same time; second, the charging circuit is never broken; and, third, the dischargingcircnit is never interrupted nor its pressure varied, nor any portion of the batteries short-circuited even momentarily. To attain these objects I may arrange resistances (such as wire electrolytic cells or motors or reverse flow of cur rent) to be put into the main circuit during the change of connections. I may effect the changes of circuit necessary in the operation of my system by means of a contact-maker moved at short intervals of time.

In order to preserve the continuity of the charging-circuit during the period which elapses between the disconnection of any one section and before the next section is included, themai n is closed through aresistanceorbypath which hasbeen previously connected in multiple arc with the section about to be removed but which resistance is in turn removed after the next section of battery has been put in multi ple with it in the said main or charging circuit. Similarly in the battery itself the sec tion just charged is put in multiple with the section next about to be charged prior to the latter being removed from the battery and being replaced in the charging-main, uniformity of pressure inthe local battery being thus maintained and sudden fluctuation of its electro-motive force being prevented.

As the four sections of any group are each included in the chargingmain for equal periods, (but only one of the sections at any time being in the main, the other three being included in the local circuit,) it may be assumed that in a period of, say,twenty-four hours, each section or fourth part receives the equivalent of six hours charge, which enables a full dis charge in the local circuit to be maintained foreight hours of that time by the three sections (threefourths of a group) which are at any instant in the local. In the same way in the local circuit for any period of discharge, say eight hours, any one section is discharging for only three-fourths of the eight hours,

(six hours,) since it is periodically removed from the local circuit and put into the charging-circuit for onefourth of the eight hours, (two hours.)

Having now explained the principle of my invention, I will proceed to describe in detail the apparatus by which it is preferred to carry the same into effect, said apparatus being illustrated in the accompanying drawings.

Figures 2, 3, 4, 5, and6 are diagrams illustrating the nature and order of the operations performed in transferring the section of such a battery from the local to the main, and vice versa, in the manner above described. Fig. 7 is a front view of the apparatus; Fig. 8, a view of one side, and Fig. 9 a view of the other side. Figs. 10 to 15 are diagrams illustrating the various positions of the moving parts during the cycle of operations, and Fig. 16 a detail showing the meter.

A, B, G, and D represent sections of a battery, each section consisting of any convenient number of cells. In Fig. 1 section A is shown included in the charging circuit H H, and sections B, O, and D included in the local or discharge circuit H". Before disconnecting the section A from the charging-circuit a resistance, Y, is put in parallel with it, as indicated in Fig. 2, the sections B, C, and D remaining in the local circuit, as before. The section A is now out out of the chargingmain, as indicated in Fig. 3, all the other conditions remaining asbefore. Section A is then inserted in the batteryin parallel with section B, which is next in turn for charging, as indicated in Fig. 4, the other conditions remaining as before. Section B is then taken out of the battery and left isolated, as indicated in Fig. 5, the other conditions remaining as before. Section B is then put in parallel with. the resistance Y in the charging-main, as indicated in Fig. 6, the other conditions remaining as before. The said resistance is then removed and the section B receives its charge, and a similar cycle to that already described with regard to section A is thus commenced. This process goes on and each of the sections continues to receive in turn its increment of charge. These changes are effected by any suitable mechanism for changing the circuits, as described, (applied to each group of storage batteries.) For example, such mechanism may consist of a rotating cylinder or drum on the periphery of which are contact-makers arranged to make connection between thecharging-main and the sections of the group of secondary batteries and the resistance in the order described; orI may use an arrangementofconr mutator such as is illustrated in Figs. 7 to 15 wherein cams driven by a suitable-timed motor and mechanism operate rocking levers to insert contact-makers between contact-terminals belonging to each section of battery and to the main and local circuits in the order necessary for effecting the connection and disconnection of batteries as described with reference to Figs. 1 to 6. I will now proceed to describe this arrangement with the aid of Figs. 7 to 15. As shown in the said figures, the positive and negative terminals of each battery are each connected to a separate contact-strip, which is fixed to the base-plate of the machine. On each contact-strip are four spring-contacts, each arranged to make contact with contact pieces on four vibrating levers, A B O D. The contact-strips and spring-contacts of the set of batteries c are marked a and (F, respectively, Figs. 10 to 15, the strips and spring-contacts of batteries Z) are marked b and b, and so on. The four vibrating levers each carry branches from both the positive and negative of the main and the positive and negative of the local, they being led to contact-strips secured to the backs of the levers. The said levers are operated by cams carried by shaft 17, one of which is shown at D Fig. 8. The order of vibration of the levers to produce the changes illustrated by Figs. 1 to 6 is illustrated diagrammatically by the companion Figs. 10 to 15. In these diagrams, for the sake of greater clearness and simplicity, but two spring-contacts of each of the contactstrips a (F W Z), &c., are shown. The contact-strips of lever A are marked a a (6*, &c., and those of lever B are marked b b I)", 850. Suppose the batteries c are in the charginginain, as in Fig. 1, then lever A will bein the position shown in Fig. 10, its contact-strips touching the springcontacts of all the batteries. The other levers, B, O, and D, are at this time lifted clear of the corresponding spring-contacts. The branches 31 and M from the main are fastened to strips a a, respectively, on lever A, and batteries a are thus included in the charging'circuit. The branches L L from the local are attached to strips to a, respectively, so that the circuit of the local is through the batteries 1) 0 (Z by wire If, strip a", spring-contact and strip b battery b, spring contact I), strip a, contact 0*, battery 0, and so on to branch If, as clearly shown in Fig. 10. It is now desired to put a resistance in parallel in the main with the section A, as in Fig. 2. To effect this I employ a rocking lever and mercury-cups, as shown at S. (The mechanism by which the said rocking lever is operated is hereinafter described.) This rocking lever is caused to assumea horizontal position, as shown in Fig. 11, thus closing the circuit through the mercury-cups y, in which the resistance isincluded, which resistance is thus placed in parallel with section A. Now it is desired to cut the section A out of the main, the resistance alone remaining therein, as in Fig. 3. This is effected by causing the dipping leverS to assume the position shown in Fig. 12, so that the circuit through y, in which the resistance is included, remains closed, while the circuit from the main through the section A is broken at z The section B is next in turn for charging, and the lever B will next be operated to put the section A in parallel with Bin thelocalcircuit, asin Fig. 4, and in Fig. 13 it will be seen that lever B has been caused to make contact with its spring-contacts, and the lever A also maintains its position.

On lever B the local wires L and L are attached, respectively, to contact-strips B and B, while strips b b are connected by a short bridge-wire, Z)", which thus serves to connect the positive terminals of battery 0 with the negative of battery a, the positive of the battery being to the local via spring a strip 6 wire II; but the positive of battery 0 is also con nected with the negative of battery I) through strip a" on lever A, the positive of the latter being connected to local through 12 a D Thus batteries a and b are in parallel in the local circuit, as in Fig. 4. On lever B the branches M M of the main are attached, respectively, to strips b" b", but the branch of the main being broken at .2 only the resistance Y remains therein.

In Fig. 5 the section B is isolated. This is efi'ected, as in Fig. 14, by withdrawing the le ver A, which leaves the section A in the local circuit. The connection between the sections A and G is made by the bridge-wire Z) on B, which has before been alluded to. The dipping lever S remains as in Fig. 12.

Fig. (3 shows the section B put in parallel with the resistance in the charging'main, and this result is arrived at by the dipping lever S assuming a horizontal position (see Fig. 15) when the main current flows to the batteries by way of a, and also through the resistance Y by way of the mercury-cups The next operation consists in withdrawing the resistance from the main. This is effected by causing the dipping lever to assume the position shown in Fig. 10. The section B will then receive its charge and commence a similar cycle to that undergone by the section A, being also operated by the dipping lever b and by the levers B and C in a similar manner to that in which the levers A and B are operated with regard to section A, and from the preceding description the similar operations of charging the sections 0 and D will be readily understood.

In Figs. 7 and 8 the construction and rangcment of the several contact-strips (4 a", &c., and the vibrating levers, and the course of the several circuits are clearly shown. The branches M hr of the main are led, respectively, to contact-plates (l and I-[, while the branches If L ot the local are led, respectively, to the contact-plates I and Ii. Each of these contact-plates is connected by a separate wire with each of the levers A B O D, so that each lever carries a branch of both the main line and the local. The wire leading from the several plates G H I K to the several levers A B G D are marked 5/ g 9 g h 72? h h, and so on. The circuits of the main are represented by full lines; those of the local by broken lines.

With this particular disposition of regulator-contacts, in order to insure that each section of the group of batteries shall receive equal charges it is evidently necessary that after having charged sections A, B, G, and D for equal periods of time instead of going back immediately to C from D and charging it and A in the order named, and so on,wh ereby the groups D and A would only receive half of the charge of their fellows, I cause D (or A) to remain for another period in connection with the charging-circuit, and thereby receive an equal charge. Thus it will be seen that the sections are connected with the charging-circuit in consecutive equal periods of time in the order indicated by the arrangement of letters following: A B O D, D O B A, A B O D, D O B A, and the battery which receives the last charge of one series of charges receives also the first charge of the following series, and therefore receives a charge during a period of double the ordinary duration; hence in a period of twenty-four .hours each battery reeeives equal increments of charge.

It now remains to describe the mechanism for driving the cams A B G D which actuate the levers, and the timing apparatus which insures that the cams shall be operated at certain regular intervals electrically.

A shaft, 17, is carried in bearings 18. Upon this shaft is secured a ratchet-wheel, 19. (See Fig. 9.) A pawl, 20, is connected by the link 22 to'thc armature 27 of the solenoid 2l,which receives an energizing-current at certain regular intervals,which causes the descent of the armature 27, which rotates intermittently the shaft 17 and its cams A B O D through an eighth of a revolution, thus causing the levers A B O D to operate to open and close circuits in the manner described with reference to Figs. 11 to 15. One of the levers, D, and a set of contacts are shown in side elevation and plan in Fig. 8, whence it will be seen that the contacts are made by rotating the cam D so as to permit the spring 23 to pull the lever on which it acts into the contacts, the cam causing disconnection by forcing the said lever out from the contacts against the pull of the spring 23. To insure that-the cams shall not make more than an eighth of a revolution, owing to the inertia of parts, I provideastop-wheel, 24, provided with a banking-piece, 25, which is held up by the rod 26, attached to the armature 27 of'the solenoid 21. Immediately after the armature has in descending commenced to rotate the shaft 17 the banking-piece 25 is lowered onto the periphery of the stop wheel 24, and so soon as the eighth of a revolution is completed the banking-piece 25 drops into a recess in the said stop-wheel and prevents further rotation. The armature 27 of the solenoid is returned to its former position as soon as the current therein ceases by the spring 28. I provide a piston attached to the armature 27 by the rod 29 and working in a dash-pot, 30, to prevent too rapid a'stroke of the armature.

The timing apparatus, which at regular intervals operates mechanism to send a current from the local circuit through the solenoid 21 to give a portion of a revolution to the shaft 17, consists of a closed drum, 33, divided radially into, say, six chambers by partitions 34. In each partition are two openings, each communicating with the adjacent chamberone, 35, near the inner circumference of the drum, and the other, 36, at about the center of the drum. The function of these holes permits of a free circulation of the contents of the drum.

Liquid is placed in the lower portion of the drum, and a small'sprocket-wheel, 37, is attached to the drum, in which wheel lies an endless chain, 38. From this wheel the chain descends, forming a sling, in which lies a weighted pulley, 40; thence it is carried round another and larger sprocketwheel, 39, on the shaft 17,and the slack is carried down to such a level that it may have to ascend to the small sprocket-wheel 37, and thus havesufiicient circumferential contact upon it. The weighted pulley 40 rotates the drum 33 with the liquid within it until the moment of the liquid about the center on which the drum rotates is sufficient to balance the turning moment induced by the weight. Then the liquid gradually trickles through the holes 35, and by this redistribution of weight permits the weighted pulley 40 to fall slowly and the drum to rotate slowly until the roller 41 on the end of rod 42 falls into a recess, 43, cut in a disk, 44, attached firmly to the said drum. The dipping lever S oscillates on a center, 8. and is weighted at 45. The rod 42 is attached to this lever, and as soon as the roller 41 enters the recess 43 the weight 45 causes the lever S to assume a position opposite to that which is shown in Fig. 9, thereby breaking the circuit of the charging-main at 2, (see description of Figs. 10 to 15,) and introducing (by the mer cury-cups y) a resistance as an alternative path for the main,and by the cups 46 close a shunt from the local or charging circuit through the solenoid 21 operating the cam-shaft 17, as hereinbefore described. On the descent of this armature 27 the rod 31 comes into contact with the spring 32 and compresses it without operating the lever S, which is upheld by a spring-detent, 48,and by the time that the rod 31 reaches a certain point the collar 47, by coming into contact with the curved surface 49, forces out the detent 48 and permits the oscillatinglever Sto return to the position indicated in Fig. 9, cutting at 46 the shunt from the local circuit through the electro-magnet 21, and permitting the spring 28 to return the armature 27, as hereinbefore described, and also cutting out the resistance by breaking the circuit at y and remaking the main circuit through 2.

It is desirable to combine a registering device with the shaft 17, as thereby an accurate account of the amount of energy used at the installation may be obtained.

It will be understood that the cycle of operations described-that is to say, the periodic transference of each group of batteries from the IIO main to the working circuit and back againgoes on continuously. In other words, the shaft 17 keeps up its intermittent rotation at all times; but there are times when, because the batteries are fully charged or for other reasons, the whole installation is cut off from the main, as will more clearly appear by reference to my application (Case 0) tiled July 16, 1888, Serial No. 280,020. Again, it may be that the supply company is not furnishing the quantity of current its contract calls for. In such cases it is evident that the consumer is either not getting any energy at all, or is getting less than he is entitled to, and therefore should not be charged during such periods. If, however, the revolutions of shaft 17 be recorded during and only during such time as the full amount of current is passing through the batteries at that particular point, it is obvious that proper charge to the consumer can be accurately computed therefrom. This is accomplished by means of the device shown in Figs. 7 and 17.

The solenoid 56 is included in the same branch of the main line as batteries when being charged, and consequently is energized whenever there is a current tlowing in that part of the main. The armature 52 of this magnet is connected with aspindle, 50, carrying a small worm-wheel, 51, so that when the maximum current is passing the armature raises the worm'wheel 5i, bringing it into eugageinent with the worm 57 on shaft 17. Spindle 50 is thereby rotated with shaft 17, and by gears 58 59 actuatcs the registering device 54. Then, however, there is no current in magnet 56, the armature 52,and with it spindle 50, drops, wheel 57 being caught and held stationary by stop-pin 55. Then, though shaft 17 continues to rotate, no account will be kept thereof. The same thing will occur if the charging-current falls below that called for by the terms of the contract. It therefore is to the interest of the company to keep the current up to the standard.

I have described my said invention in the form in which a resistance is inserted as bypath during the period during which the pro cess of changing the connections of the sections of the battery is going on, This will generally be found to be the cheapest arrangement and one that for practical purposes is sufficient; but it is evident thatinstead of this resistance one might use an extra section of the battery, which would then have to be made with two sections more than were neces sary to furnish the pressure required in the utilization-circuit. There would then at all times (except during the moments when the changes of connection were taking place) be aseetion which was connected neither with the charging nor discharging circuit, and the cycle would naturally be varied to suit this state of things, the simplest mode being first to place this extraction in parallel with the section about to be charged, then to isolate the latter, then to place it in parallel with the section which has just been charged, and then to isolate the latter, so that it will be ready to be connected with the battery at the next change.

I have also described the actuating mechanism of the periodic change of connections as being driven by the charging-circuit or the local battery. I consider that the latter is de cidedly the most advantageous mode of actuation; but it is evident that it is not essential that it should be electrically driven. If the circumstances are such that there is no obj ection to the use of clockwork, the changes of connection may be made at stated intervals by ordinary mechanism of that kind.

The present application may be regarded as a division and continuation of my application filed June 21,1888, Serial No. 277,712, in which the apparatus herein described is set forth but not claimed. I do not claim herein the subject-matter of said prior application; neither do I claim the particular timing mechanism described, as that forms the subject-matter of another application for patent, to wit, Serial No. 280,371, filed July 19, 1888; but

\Vhat I do claim herein, and desire to secure by Letters Patent, is-

1. In a system of electrical distributiomthe combination of a closed main charging-circuit, a local working circuit, two or more groups of secondary batteries, positive and negative terminal contatts for each set of batterie=,switclr levers, one for each group of batteries, con tact plates on each lever for connecting with all the battery-terminals, and means for vibrating said levers so as to transfer each set or group of batteries from one circuit to the other in regular order, substantially described.

2. The combination of a closed chargingcircuit, a working-circuit, two or more groups of secondary batteries, a branch circuit including a resistance approximately equal to that of each set of batteries, terminal contact strips for the several sets of batteries, switch mechanism-such as a series of switch-levers-. fortransferringthe several sets ofbatteries from one circuit to the other, and timing mechanism controlling said switch mechanism, and also controlling contacts in the circuit of said resistance, whereby the latter is included in the main when there is no battery therein, substantially as described.

3. The combination of a closed chargingcircuit, aloeal working-circuit, two or more sets of secondary batteries, terminal contactstrips for each set of batteries, a series of vibrating switch-levers carrying each contactstrips constituting terminals of branch circuits of both the main and local, and other contact strips adapted to connect the terminals of different batteries, and mechanism for vibrating said levers into and out of contact with the terminals of said batteries, thereby transferring them from one circuit to another, substantially as described.

4. In a system of electrical distribution, the combination, with the main circuit, the work:

XIO

ing'eircuit, and two or more groups of batteries adapted to be included in either circuit, of a seriesof switches for transferring said sets of batteries from one circuit to another, eontinuously-operating timing mechanism for operating said switches at stated intervals, a resistance, and circuit connections, also controlled by said timing mechanism for including said resistance in a branch of the main circuit in parallel with each set or group of batteries in the act of transferring the same from one cireuitto the other, substantially as described.

5. The combination, with theclosed main circuit and charging-circuit, of two or more sets of secondary batteries, a series of contact strips-two for each set of batteriesa series of switch-levers having strips constituting terininals of branches of both the main and local and other strips for connecting the terminals of different batteries, a rotatory shaft having aseries of earns--one for each lever-and means for rotating said shaft at a uniform speed, whereby at regular intervals said levers are connected with and disconnected from said battery contact-strips and the several groups of batteries included for a determined period in the charging'cireuit, substantially as described.

6. The combination, with themain circuit, working-circuit, and batteries, ofswiteh mechanism for including the batteries at regular intervals in the working-circuit, a shaft rotating at a uniform rate and controlling said switch mechanism, a registering device, an electro magnet in the chargingmain, and connections between said registering device and said shaft controlled by said magnet, so that the dura tion of charge of the normal current is registered, substantially as described.

7. The combination, with the rotating shaft for operating a circuit-changer and timing mechanism controlling said shaft, registering device, an electro-magnet, and gearing for operating said registering device, connected with the armature of said magnet, so as to be thereby thrown into and out of engagement with said shaft, substantially as described.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

HENRY EDMUNDS.

\Vitnesses:

PHILIP DIAURO, O. J. HEDRIOK. 

